This second book in the Gallagher Girls series takes place the second semester of Cammie's sophomore year. She is still getting over breaking up with Josh. But things are changing at the Gallagher Academy for Extraordinary Young Woman. This semester boys are coming in an exchange from the boys' training school for spies. Cammie is thrown when one of boys--Zach--seems to be taking a personal interest in her. Or is he? Cammie doesn't speak boy and so there are lots of opportunities for misunderstandings between the two of them. After all, he is a spy too. It doesn't help that once the boys arrive, the school goes into Code Black. Apparently someone is trying to break in or out--and this time it isn't Cammie. Cammie and her friends are determined to find out what it going on, even if it means bugging the boys' rooms. This was another fun episode in an entertaining series about a group of young geniuses who are learning to be spies.